import fs from "then-fs";
fs.readFile('./1.txt','utf8').then((r1)=>{
    console.log(r1)
   return fs.readFile('./2.txt','utf8')
})
.then((r2)=>{
    console.log(r2)
    return fs.readFile('./3.txt','utf8')
})
.then((r3)=>{console.log(r3)})